Design of a Flextensional Transducer with Adjustable Prestress

Abstract

Prestress has a great bearing on the performance of flextensional transducer. In order to enhance the adjustability of prestress, a design method for the flextensional transducer with adjustable prestress was proposed in this study. Through the conversion design of rotational and rectilinear motions of the transition block, the clamping length of major axis of class IV flextensional transducer shell was changed, enabling the adjustment of prestress. Next, the related experiment was further carried out. The results show that the return displacement of adjustable transition block is slightly greater than the travel displacement, and both displacements show high overlap ratios in the two tests. Because of the prestress adjustment, the frequency response of flextensional transducer is reduced to some extent, within one frequency band (40-63 Hz), but its sound pressure level (SPL) substantially increases nearby the resonant frequency (about 75 Hz).